Ultralight graphene aerogel enhanced with transformed micro-structure led by polypyrrole nano-rods and its improved microwave absorption properties

Facile Fabrication of Three-Dimensional Lightweight RGO/PPy Nanotube/Fe3O4 Aerogel with Excellent Electromagnetic Wave Absorption Properties

“…Therefore, the EM wave absorption properties can be tuned by adjusting the thickness of the samples according to specific applications. 3 In Figure 7, the maximum RL values of GA, GFA, GPA, and GPFA are −37.8 dB at 7.8 GHz with a thickness of 4.5 mm, −47.1 dB at 8.15 GHz with a thickness of 4.5 mm, −40.2 dB at 9.35 GHz with a thickness of 3.5 mm, and −49.2 dB at 11.8 GHz with a thickness of 3 mm, and moreover, the bandwidths of RL below −10 dB are 3.7, 4.3, 3.95, and 6.1 GHz in the range of 6.2–9.9, 6.65–10.95, 7.75–11.7, and 9.8–15.9 GHz, respectively. It can be found that the addition of both Fe 3 O 4 nanoparticles and PPy nanotubes is helpful to improve the EM wave-absorbing property of the RGO aerogel, and furthermore, the ternary GPFA exhibits the best EM wave absorption performance because of the introduction of multiple dissipation ways.…”

“…18,33 In addition, PPy nanotubes and Fe 3 O 4 nanoparticles attached on twisted graphene sheets provide RGO sheets with more defects, and thus, the composite will introduce more defect polarization relaxation processes. 3 Because the calculated density of GPFA is about 38.3 mg/cm 3 , it can be used as good ultralight EM wave absorption materials.…”

“…1,2 Nowadays, EM wave-absorbing materials with intense absorption ability, broad absorption bandwidth, ultralight weight, and thin thickness are in high demand. 3,4 Recently, graphene has been widely used as an EM wave-absorbing material because of its excellent properties, such as low density, high specific surface area, large aspect ratios, and versatile processing. 5,6 According to the EM energy conversion principle, a proper matching between the dielectric loss and the magnetic loss determines the reflection and attenuation characteristics of EM wave absorbers.…”

Fabrication of PPy Nanosphere/rGO Composites via a Facile Self-Assembly Strategy for Durable Microwave Absorption

“…The tedious functionalization steps are avoided due to the specific π–π interaction between PPy nanospheres and GO. Compared with many previous reports about PPy/graphene [30,32,33], the self-assembly strategy in our work has some unique advantages in controlling composition, saving time, and increasing yield. The as-prepared PPy nanosphere/rGO composites with different mass ratios are investigated in detail.…”

“…It is confirmed that the reinforced dielectric relaxation, special structural characteristics, and the charge transfer between conjugated polymer and rGO, are primarily responsible for the enhanced microwave absorption of these conjugated polymer/rGO composites. Among them, PPy/rGO composites are becoming the most typical representatives rendered by their diversified assembly modes and microstructures [32,33]. In our previous work, PPy nanospheres have displayed their own functions in optimizing the characteristic impedance and intensifying the reflection loss properties of PANI [34].…”